Automatic firearm



Get. 14 1924.

J. M. BROWNING AUTOMATIC FIREARM Filed Sept. 21 1923 fnvaniar I Patented Oct. 14, 1924.

UNITE STATES JOHN M. BROWNING, OF OGDEN, UTAH.

nuromrrc FIREARM.

Application filed September 21, 1923. Serial No. 664,068;

To all whom it may com-em:

Be it known that I, JOHN M. BROWNING,

a citizen of the United States, residin in Ogden, in the county of Weber and tate of Utah, have invented certain new and useful Improvements in Automatic Firearms, of which the following is a specification, reference being had to the accompanying drawings, forming a part hereof.

The invention is for improvements in machine guns and the like in which all operations of the mechanism, except that of the trigger, are automatically effected, andhas for 1ts object to provide means for re lating or retarding the rate of firing, while retam-ing the automatic action.

It has. been found that in automatic machine guns, and articularly in automatic machine rifles, as heretofore constructed, the

29 rate of firing may be so rapid-when the or rifie is being operated with its full automatic action, that is, when the trigger is being held back, as to be a positive disadvantage. The rate of firing may be so rapid that the shooter can not properly aim his gun or rifle, ammunition iswasted and the rapid succession of recoils is so severe, particularly in the case of a machine rifle being shot from the hip or shoulder, that the accuracy of the shooter is much decreased. Also, particularly in the case of the automatic rifle, the gun heats up too rapidly and the rifiing in the barrel Wears out quickly. It has therefore been found advisable to retard the rate of firing by insuring that there should be a lapse of time between successive shots greater than the time required for the usual recoil and return to battery of the recoiling parts.

To that end I provide novel means which retard or slow down the rate of firing by preventing the return of the firing mechanism to battery after recoil until after the lapse of a desired period of time. According to my present invention, on the firing of a shot the retarding mechanism is moved into operative position to insure that the firing mechanism shall be cooked on the recoil thereof and to positively prevent the firing mechanism from being released to fire the next shot until the retarding mechanism has moved from operative to inoperative position, and the time taken for this movement of the retarding mechanism from and described in m operative to inoperative position can be regulated to insure the desired lapse of time between shots.

I illustrate my invention as applied to the automatic machine rifle such as is shown United States Patent No. 1,293,022, and t e accompanying drawings show those parts of the machine rifle of said patent to which my new invention is applied.

In the accompanying drawings, Fig. 1 represents a longitudinal vertical section of the central portion of the machine rifle with the arts in firing position and certain parts in e evation.

Fig. 2 representsa plan view of the trigger casing and its accompanying parts.

Fig. 3 represents a vertical longitudinal section of the retarding mechanism with the sear and action-slide in cocked position after recoil.

Fig. 4 represents a lo 'tudinal vertical section of a portion of t e action-slide, a portion of the trigger-guard, and the trigger and sear in cocked position.

Fig. 5 represents a left hand side view of the retarding lever latch and of the right hand rear portion of the retarding lever, with a portion of the retarding lever in section.

Fig. 6 represents a front view of the escapement ratchet and pawl.

Fig. 7 represents a vertical transverse section in the line 7-7 of Fig. 1.

The following main parts of the machine rifle shown and described in the Patent No.

1,203,022 are shown in the drawings:

The hammer 1; the action-slide 2; pistonrod 3; piston 4; reaction spring 5; bufier plate 6; breech casing 7; butt stock 8; magazine release 9;magazine catch 10; magazine 11; trigger 12; trigger-plate or guard 13; and sear 14.

The trigger is pivoted at its forward end on pivot-pin 12 which extends transversely through the trigger-guard. In Figs. 1, 3 and 4 the trigger is shown in its normal inoperative position, to which it is returned by the sear spring after being pulled back to unlock the firing mechanism as hereinafter described. Rearward projection 12" engaging the trigger-guard prevents the trigger from swinging down beyond the position shown in Figs. 1, 3 and 4.

enga es at its forward end the fixed The s ear 14 is pivoted on pin 14; seated whic projects transversely throug the trigger-guard under the pin 14". As shown in Fig. 1, said spring normally holds the sear in its rearward position with its rear arm in raised position and the pivot pin 14 in engagement with the front face of the slot 14", whereby the end of the rear arm of the sear will engage the cocking shoulder 2' on the bottom face of the actionslide when the action-slide moves forward after its recoil, and hold the action-slide and hammer cocked until the front arm of the sear is raised by the trigger as hereinafter described. In Figs. 1, 3 and 4 the trigger is in its normal, inoperative position, and if the retarding lever 19 is in its inoperative position, as hereinafter described, a rearward pull on the trigger will bring the top of the upwardly projecting arm 12 of .the trigger into engagement with the end of the forward arm of the sear, rock the scar on its pivot and free the action-slide and hammer for forward firing movement under the action of the spring 5.

Pivoted on in 17, which projects transversely throng the trigger guard, is the combined ratchet 17 and escapement wheel 17 (Fig. 6). An escapement pawl 18 is pivoted on pin 18, which pro ects transversely through the trigger guard below pivot pin 17 Said escapement pawl is positioned for engagement with the teeth of the escapement wheel 17.

19 is a retarding and trigger-locking lever pivoted at its rear end and centrally of the trigger guard on pin 19 which projects transversely through the trigger guard. Pivotally mounted on the forward end of the retarding lever and projecting downwardly therefrom is the ratchet pawl 20 having teeth 20- to engage the teeth of the ratchet 17 Seated in the head of the retarding and trigger-locking lever is the ratchet pawl spring 2O having its upper end seated against a rearward projection on the ratchet pawl and thereby pressing the lower end of the pawl rearwardly and holding the teeth of said pawl in engagement with the ratchet 17 that the retarding lever is not parallel with the sides of the trigger-guard throughout its length, but for a portion of its length is inclined to the left, whereby its front end is in a vertical line with the ratchet 17", so that the ratchet pawl 20 can properly en- It will be noted (see Fig. 2)

sure to rotate the forward end of the retarding lever upwardly, from the position shown in Fig. 1 to that shown in Fig. 3.

Projecting laterally from the right hand side of the rear end of the retarding lever and integral therewith is lever piece 19 with longitudinally extending front and rear arms (Figs. 2 and 5).

Between the upwardly projecting arm 12 of the trigger and the ri ht hand side of the trigger-guard, and just orwardof the lever piece 19, is the retarding lever latch 21, pivoted on a fixedpin 21", which projects inwardly from right hand side of the trigger-guard. Seated in said latch is the latch spring 21 hearing at its lower end against the trigger-guard, as shown in Fig. 5. In the rear face of said latch is a recess 21. As will be seen by reference to Fig. 5, the latch spring normally holds said latch in its rearward position with the shoulder of said recess 21 engaging the top face of the shelf 19 on the end of the front arm of the lever piece 19 when the retarding lever is inits lowered position (Fig. 1), thereby holding the retarding lever in its lowered or operative position, as shown in Fig. 1. The shelf 19 on the end of the front arm of the lever piece'19 projects laterally and to the right, beyond the inner edge of the longitudinal right hand ledge 13 on the top right hand side of the trigger-guard, as shown in Fig. 2. The upward movement of retarding lever 19 is limited by the rear end of lever piece 19 engaging the top face of the trigger-guard, as shown in Fig. 3. The downward movement of retarding lever 19 is limited by engagement of the shelf 19 13th the top of the said longitudinal ledge The top of the trigger adjacent the arm 12 forms a shoulder 12 (Fig. 7) which, unless the retarding lever is in its uppermost or inoperative position, will engage the bottom face of said lever before the top of the arm 12 will engage the front arm of the sear.

The pivot pins 14*, 19", 12" and 17 are held in their seats when the rifle is assembled by the sides of the breech casing.

The operation of the retarding device can now be readily understood. In Fig. 1 the parts are in the position which they assume when a shot is being fired. Upon the firing of a shot the action-slide immediately recoils and just as it moves forward after the limit of recoil, the rear end 'of the sear engages the cocking shoulder 2 holding the action-slide and hammer cocked. The action-slide, by its cocking shoulder, strikes the rear end of the sear a sharp blow as the action slide shoots forward under the pressure of its reaction spring 5. The force of this blow will be buffered and the danger of injuring the parts thereby avoided by the longitudinal movement of the sear, permitted by its pivot slot 14 against the rearward pressure of the sear spring. Moreover, the

front end of the sear in moving forward from the position of Fig. 1 to that of Fig. 3, will strike the rear face of latch- 21, rotate it on its pivot against the pressure of its spring and disengage the shoulder of recess 21 from engagement with the shelf 19 on the forward arm of the lever piece 19 Retarding lever 19 is now free to swing upwardly under the influence of its spring 19 On the upward swing of the'retarding lever the teeth on the ratchet pawl .20 engage the ratchet 17 rotating the ratchet and the escapement wheel 17, the teeth of which engage with the escapemerit pawl 18, which operates in a, well-known manner to retard the rotation of the escapement wheel, thereby retarding the u ward movement of the retarding lever. ntil the retarding lever has reached its uppermost position, pull on the trigger can not bring arm 12 on the trigger into engagement with the sear to rotate the sear and release the action-slide because of the position of the retarding lever overlying the shoulder 12 on the trigger. When the retarding lever has reached its uppermost position, however, as in Fig. 3, upon pulling the trigger the projection 12 will engage the front end of the sear before the shoulder 12 will strike the bottom of the retarding lever and the action-slide and' hammer will be released to move forward to fire the next cartridge.

On the forward motion of the action-slide the bottom of the slide engages the top of the retarding lever, forcing it down to its low ered position (Fig. 1) against the pressure of its spring. The retarding lever will swing downward so rapidly that the teeth on pawl 20 will ride over'the teeth on ratchet 17 b and there will be no appreciable retarding of the forward movement of the action-slide. If the trigger is being held back for full automatic action the retarding lever, on its downward swing, will engage the shoulder 12 on the trigger and force the trigger downwardly against the pull of the operator and thereby insure that the sear will return to and remain in cooking position until the re-' tardinglever has again returned to its up permost and inoperative position. By continuing to pull back on the trigger the rate of firing can be made as rapid as the operation of the retarding mechanism permits. \Vhen the action slide moves forward, the sear, actuated by its spring, is returned to its rearward position with its rear end raised for again engaging the cocking shoulder of the action-slide on the next recoil thereof. Rotation of the sear on its pivot pin under the influence of its spring is limited by the stud 22, which projects upwardly from the top face of the trigger-guard and which is engaged by the bottom face of the front arm of the sear when the sear is in its normal position, as shown in Fig. 7.

When the retarding lever is lowered, the front face of the shelf 19 rides over the rearwardly inclined face of the catch 21, rotating said catch forwardly against its spring, until the retarding lever reaches the limit of its downward movement, when said shelf registers with the recess 21 of the latch and the latch snaps back with its shoulder engaging the end of the shelf, holding the re tarding lever in its downward position as shown in Figs. 1, 2 and 5, until the latch is again engaged and pushed out of locking position by the longitudinal movement of the sear, as hereinbefore described.

The minimum length of time elapsing, therefore, between shots (Without counting the very brief time consumed in, the recoil and return of the firing mechanism) will be the length of time taken by the retarding lever in rising from its lowered 0r operative position to its raised or inoperative position,

vand this will be governed by the weight of the escapement pawl andby the number of teeth in the ratchet pawl and escapement wheel. a

The retarding lever andits spring can be removed from the trigger-guard without affecting the operation of the gun except that there will then be nothing to retard the rate of firing. By holding back the trigger the sear will be kept from any cooking engagement with the action-slide, permitting full automatic action. A

It will be noticed that when my retarding mechanism is operating, a continued pull on the trigger is essential for full automatic ac tion, as i the case when the retarding mechanism is dispensed with.

\Vhat I claim. and desire to secure by Letters Patent is: 7

1. In anautomatic fire-arm the combination of recoiling firing mechanism, a sear, a trigger, and firing retarding mechanism comprising trigger locking means rendered operative on the forward firing movement of the firing mechanism to lock the trigger from sear actuating movement, means to move said locking means to inoperative position, means which render said moving means operative on the motion of the firing mechanism following discharge and means for retarding the movement of said locking trigger I p 'meansfrom operative to inoperative posltion, whereby the minimum time elapsmg between shots may be increased.

2. In an automatic fire-arm the combination of recoiling firing mechanism, a sear, a trigger, and firing retarding mechanism comprising trigger locking means rendered operative on the forward firing movement of the firing mechanism to lock the trigger from sear actuating movement, means for automatically locking said trigger locking means in said operative position and which is released by the cocking of said firing mechanism following discharge, means for moving said trigger locking means to inoperative position upon the release of said locking means, and means for retarding the move-' ment of said trigger locking means from op erative to inoperative position 3. In an automatic fire-arm, the combination of recoiling firing mechanism, a sear, a trigger, and firing retarding mechanism comprising trigger-locking means rendered operative to lock the trigger from sear-actuating movement on the forward firing move-. ment of the firing mechanism and means rendered operative by the cocking of said firing mechanismfollowing recoil to move the trigger-locking means to inoperative position, whereby after each shot the trigger will be locked from sear-actuating movement until after the firing mechanism has been cocked by the sear.

4. In an automatic fire-arm, the combination of recoiling firing mechanism, a sear, a trigger, and firing retarding mechanism comprising -a trigger-locking element rendered operative on the forward firing movement of the firing mechanism to lock the from sear-actuating movement, means rendered operative vby the cocking movement of said firing mechanism to move said trigger-locking element from operative to inoperative position, and means for retarding the said movement of said triggerlooking element, whereby on the firin of each shot said trigger will be locked om sear actuating movement until said element has moved from operative to inoperative position and whereby the time taken for such movement will be increased.

5. In an automatic fire-arm, the combination of recoiling firing mechanism, a sear, a trigger and firing retarding mechanism comprising a spring-pressed trigger-locking element moved to operative position against the pressure of said spring on the forward firingmovement of the firing mechanism to lock the trigger from sear-actuating movement, means for locking said element in its said operative position rendered inoperative on the cooking movement of said firing means, and means for retarding the rate of movement of said element from operative to inoperative position, whereby on the firing of which retards said movement of said lever from operatlve to moperatlve pos1t10n, 2;

each shot saidtrigger will be locked frdm sear-actuating movement until afterthe firing mechanism has beencocked by the sear and whereby'there will be a lapse of time betweenshots at least equal to; the time taken for said trigger-locking element to move from operative to inoperative position.-

6. In an automatic fire-arm, the combination of recoiling firing, mechanism, a' trigger, a sear mounted .for limited longitudinal movement, a spring-pressed trigger-locking lever actuated by the firing mechanism on. its forward firing movement to operative position against thepressure of its spring, a lever catch to engage said lever and hold it in trigger-locking position and which is positioned to be'disengaged from said lever by the forward movement of said sear, whereby when the firing mechanism engages the scar on its cocking engagement therewith said sear will engage said catch to release said lever for movement to inoperative posi-. tion under the influence of its spring. 7 In an automatic fire-arm, the combina-' tion of recoiling firing mechanism, a sear, a trigger, and fire-retarding mechanism comprising a movable trigger-locking element, a spring therefor, means for retarding the movement of said trigger-locking element fromoperative to inoperative position, means for locking said element in its opera tive position, said element being moved to operative position against the pressure of its spring by said firing mechanism on its forward firing movement and being held in said position by said locking means, and means actuated by said firing mechanism on its cocking movement to disengage said locking means. p

8. In an automatic fire-arm, the combination of recoiling'firing mechanism, a trigger, a sear having limited longitudinal movement, yielding means for normally holding said sear in its rearward position, a triggerlocking lever actuated by the firing mechanism on its forward firing movement to lock the trigger from sear-actuating movement, lever-locking means which looks said lever in its operative position, said locking means being positioned to be engaged by the sear when said sear is in its forward position, whereby when the sear and firing mechanism come into cocking engagement the sear. will bemoved forwardly and will engage said locking means, thereby unlocking said 120 lever.

9. In an automatic fire-arm. the combination of recoiling firing mechanism, a trigger, a sear, a trigger-locking lever, means for moving said lever to operative position on 125 the firing of a shot, means for moving said lever from operative to inoperative position, escapement means engaged by said lever latch for locking said lever in its operative position, and means actuated by the firing mechanism on its cocking movement for disengaging said latch from locking engagement with said le\'er, as and for the purpose described.

10. In an automatic fire-arm, the combination of recoiling firing mechanism, a trigger, a sear having limited longitudinal movement, a trigger-locking lever, means for moving said lever away from operative position, means for retarding said movement of said lever, and a latch which locks said lever in its operative position and which is actuated to unlock said lever by the forward movement of the sear following cocking engagement with the firing mechanism.

11. In an automatic fire-arm, the combination of recoiling firing mechanism, a trigger, a scar having limited longitudinal movement, yielding means to normally hold said sear in its rearward position, a trigger-locking lever actuated by the firing mechanism on its forward firing movement to operative position to lock the trigger from sear-actuating movement, means for moving said lever from operative to inoperative position, a

-yieldingly mounted latch which locks said lever from movement when in its operative position and which is positioned to be engaged by the sear when said sear is. in its forward position, whereby the firing mechanism will be cocked by the sear after each recoil and whereby the forward motion of the sear following the cooking engagement of sear and firing mechanism will both buffer the blow of said engagement and will disengage said latch from said lever, permitting said lever to. move to inoperative position to unlock the trigger.

12. In an automatic fire-arm, the combination of recoiling firing mechanism, and fir- .ing retarding mechanism comprising a locking lever, means rendered operative by the firing mechanism on its initial forward movement following recoil to move said lever from looking to unlocking position, means for retarding said movement of said lever, and means for'moving said lever to .locking position on the further forward movement o said firing mechanism.

13. In an automatic fire-arm, combination of recoiling firing mechanism, a sear, a trigger, a locking lever which is moved by the firing mechanism on its forward firing movement to operative position overlying the trigger, a latch to engage and lock said lever in said position, a lever spring, means actuated by the firing mechanism on its initial forward movement following recoil to disengage said latch from said lever, escapement means engaged by said lever to retard the movement of said lever from operative to inoperative position.

14. In an automatic fire-arm, combination of recoiling firing mechanism, a sear having limited longitudinal movement, a. trigger, and firing retarding mechanism comprising a locking lever, a lever spring, a lever locking latch and escapement mechanism engaged by said lever, as and for the purpose described.

15. In an automatic fire-arm, combination of recoiling firing mechanism and firing retarding mechanism comprising a lever rendered operative on the forward firing movement of the firing mechanism to prevent actuation of the firing mechanism to fire a shot, means to move said lever from operative to inoperative position, and means for retarding said movement of said lever comprising a toothed pawl carried by said lever, a ratchet wheel, an escapement wheel and pawl actuated by said ratchet, and a spring holding said toothed pawl in yielding engagement with said ratchet, the teeth on said pawl and ratchet being so organized that when in the operation of the fire-arm said lever moves from operative to inoperative position said pawl will rotate said ratchet, and when said lever is moved from inoperative to operative position the teeth on said pawl will slide over the teeth on said ratchet -without any appreciable rotation of the same.

This specification signed' and witnessed this 19th day of Sept, A. D. 1923.

JOHN M. BROWNING.

In the presence of: C. J. EHBETs,

ARTHUR L. ULRICH. 

